Study: 38% of iPhone customers come from RIM, Android

With sales of iPhones still booming, you might be wondering where all of those customers are coming from. Philip Elmer-DeWitt at Fortune is citing an April survey by the Consumer Intelligence Research Partners (CIRP) that shows that more iPhones were sold to consumers leaving Apple's competitors than to owners of earlier iPhone models.

Data from CIRP indicate that 42 percent of iPhone buyers in April were switching from another smartphone, up from 36 percent in February. 38 percent of those buyers were switching from either Android or BlackBerry -- that's up from 29 percent in February.

Buyers who were coming from a feature phone or who had never owned a mobile phone before accounted for 24 percent of the buyers, while 34 percent were upgrading from an earlier model of the iPhone. Just after the iPhone 4S launched last October, that number was at about 71 percent.